When scientists talk about the cryosphere, they mean the places on Earth where water is in its solid form, frozen into ice or snow. Read more ...

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strand crack

stratocumulus

a principal low-level cloud type (cloud genus), predominantly stratiform, in the form of relatively low gray and/or whitish layer, sheet or patch; its elements are often arranged in bands or rolls that lie across the wind; light rain, snow, or sleet may fall from stratocumulus.

stratopause

stratosphere

a layer of the Earths atmosphere, between the troposphere and mesosphere, that is stratified in temperature such that cooler layers are closer to the Earths surface, and warmer layers are higher up (opposite the pattern of the troposphere near the Earths surface); situated between about 10 to 50 kilometers (6 to 31 miles) in altitude above the surface of the moderate latitudes; at the poles, it starts at about 8 km in altitude; composition is basically the same as that of the lower atmosphere, with the addition of ozone.

stratus

a principal low-level cloud type (cloud genus) in the form of a low-altitude, light to dark gray cloud layer with a rather uniform base; generally diffuse and dull; this cloud formation has little structure and looks like fog, except that it is above the ground, stratus does not usually produce precipitation, but when it does occur, it is in the form of minute particles, such as drizzle, ice crystals, or fine snow grains.

string fen

strip

a long narrow area of pack ice, about 1 kilometer (0.6 mile) or less in width, usually composed of small fragments detatched from the main mass of ice, and run together under the influence of wind or current.

surface observation

surface temperature

the ambient temperature indicated by a thermometer exposed to the air but sheltered from direct solar radiation, or placed in an instrument shelter 1.5 - 2.0 meters (5.0 - 6.6 feet) above ground; also called air temperature.

surface wind

wind blowing near the earth's surface; it is measured, by convention, at a height of 10 meters (33 feet) above ground in an area where the distance between the anemometer and any obstruction is at least 10 times the height of the obstruction.